388 lines
11 KiB
Rust
388 lines
11 KiB
Rust
//! Multi-dimensional arrays with per-dimension specifiable lower bounds
|
|
|
|
use std::cast;
|
|
use std::vec::VecIterator;
|
|
|
|
/// Information about a dimension of an array
|
|
#[deriving(Eq, Clone)]
|
|
pub struct DimensionInfo {
|
|
/// The size of the dimension
|
|
len: uint,
|
|
/// The index of the first element of the dimension
|
|
lower_bound: int,
|
|
}
|
|
|
|
/// Specifies methods that can be performed on multi-dimensional arrays
|
|
pub trait Array<T> {
|
|
/// Returns information about the dimensions of this array
|
|
fn dimension_info<'a>(&'a self) -> &'a [DimensionInfo];
|
|
|
|
/// Slices into this array, returning an immutable view of a subarray.
|
|
///
|
|
/// # Failure
|
|
///
|
|
/// Fails if the array is one-dimensional or the index is out of bounds.
|
|
fn slice<'a>(&'a self, idx: int) -> ArraySlice<'a, T>;
|
|
|
|
/// Retrieves an immutable reference to a value in this array.
|
|
///
|
|
///
|
|
/// # Failure
|
|
///
|
|
/// Fails if the array is multi-dimensional or the index is out of bounds.
|
|
fn get<'a>(&'a self, idx: int) -> &'a T;
|
|
}
|
|
|
|
/// Specifies methods that can be performed on mutable multi-dimensional arrays
|
|
pub trait MutableArray<T> : Array<T> {
|
|
/// Slices into this array, returning a mutable view of a subarray.
|
|
///
|
|
/// # Failure
|
|
///
|
|
/// Fails if the array is one-dimensional or the index is out of bounds.
|
|
fn slice_mut<'a>(&'a mut self, idx: int) -> MutArraySlice<'a, T> {
|
|
MutArraySlice { slice: self.slice(idx) }
|
|
}
|
|
|
|
/// Retrieves a mutable reference to a value in this array.
|
|
///
|
|
///
|
|
/// # Failure
|
|
///
|
|
/// Fails if the array is multi-dimensional or the index is out of bounds.
|
|
fn get_mut<'a>(&'a mut self, idx: int) -> &'a mut T {
|
|
unsafe { cast::transmute_mut(self.get(idx)) }
|
|
}
|
|
}
|
|
|
|
trait InternalArray<T> : Array<T> {
|
|
fn shift_idx(&self, idx: int) -> uint {
|
|
let shifted_idx = idx - self.dimension_info()[0].lower_bound;
|
|
assert!(shifted_idx >= 0 &&
|
|
shifted_idx < self.dimension_info()[0].len as int,
|
|
"Out of bounds array access");
|
|
shifted_idx as uint
|
|
}
|
|
|
|
fn raw_get<'a>(&'a self, idx: uint, size: uint) -> &'a T;
|
|
}
|
|
|
|
/// A multi-dimensional array
|
|
#[deriving(Eq, Clone)]
|
|
pub struct ArrayBase<T> {
|
|
priv info: ~[DimensionInfo],
|
|
priv data: ~[T],
|
|
}
|
|
|
|
impl<T> ArrayBase<T> {
|
|
/// Creates a new multi-dimensional array from its underlying components.
|
|
///
|
|
/// The data array should be provided in the higher-dimensional equivalent
|
|
/// of row-major order.
|
|
///
|
|
/// # Failure
|
|
///
|
|
/// Fails if there are 0 dimensions or the number of elements provided does
|
|
/// not match the number of elements specified.
|
|
pub fn from_raw(data: ~[T], info: ~[DimensionInfo])
|
|
-> ArrayBase<T> {
|
|
assert!(!info.is_empty(), "Cannot create a 0x0 array");
|
|
assert!(data.len() == info.iter().fold(1, |acc, i| acc * i.len),
|
|
"Size mismatch");
|
|
ArrayBase {
|
|
info: info,
|
|
data: data,
|
|
}
|
|
}
|
|
|
|
/// Creates a new one-dimensional array from a vector.
|
|
pub fn from_vec(data: ~[T], lower_bound: int) -> ArrayBase<T> {
|
|
ArrayBase {
|
|
info: ~[DimensionInfo {
|
|
len: data.len(),
|
|
lower_bound: lower_bound
|
|
}],
|
|
data: data
|
|
}
|
|
}
|
|
|
|
/// Wraps this array in a new dimension of size 1.
|
|
///
|
|
/// For example the one-dimensional array `[1,2]` would turn into
|
|
/// the two-dimensional array `[[1,2]]`.
|
|
pub fn wrap(&mut self, lower_bound: int) {
|
|
self.info.unshift(DimensionInfo {
|
|
len: 1,
|
|
lower_bound: lower_bound
|
|
})
|
|
}
|
|
|
|
/// Takes ownership of another array, appending it to the top-level
|
|
/// dimension of this array.
|
|
///
|
|
/// The dimensions of the other array must have an identical shape to the
|
|
/// dimensions of a slice of this array. This includes both the sizes of
|
|
/// the dimensions as well as their lower bounds.
|
|
///
|
|
/// For example, if `[3,4]` is pushed onto `[[1,2]]`, the result is
|
|
/// `[[1,2],[3,4]]`.
|
|
///
|
|
/// # Failure
|
|
///
|
|
/// Fails if the other array does not have dimensions identical to the
|
|
/// dimensions of a slice of this array.
|
|
pub fn push_move(&mut self, other: ArrayBase<T>) {
|
|
assert!(self.info.len() - 1 == other.info.len(),
|
|
"Cannot append differently shaped arrays");
|
|
for (info1, info2) in self.info.iter().skip(1).zip(other.info.iter()) {
|
|
assert!(info1 == info2, "Cannot join differently shaped arrays");
|
|
}
|
|
self.info[0].len += 1;
|
|
self.data.push_all_move(other.data);
|
|
}
|
|
|
|
/// Returns an iterator over the values in this array, in the
|
|
/// higher-dimensional equivalent of row-major order.
|
|
pub fn values<'a>(&'a self) -> VecIterator<'a, T> {
|
|
self.data.iter()
|
|
}
|
|
}
|
|
|
|
impl<T> Array<T> for ArrayBase<T> {
|
|
fn dimension_info<'a>(&'a self) -> &'a [DimensionInfo] {
|
|
self.info.as_slice()
|
|
}
|
|
|
|
fn slice<'a>(&'a self, idx: int) -> ArraySlice<'a, T> {
|
|
assert!(self.info.len() != 1,
|
|
"Attempted to slice a one-dimensional array");
|
|
ArraySlice {
|
|
parent: BaseParent(self),
|
|
idx: self.shift_idx(idx)
|
|
}
|
|
}
|
|
|
|
fn get<'a>(&'a self, idx: int) -> &'a T {
|
|
assert!(self.info.len() == 1,
|
|
"Attempted to get from a multi-dimensional array");
|
|
self.raw_get(self.shift_idx(idx), 1)
|
|
}
|
|
}
|
|
|
|
impl<T> MutableArray<T> for ArrayBase<T> {}
|
|
|
|
impl<T> InternalArray<T> for ArrayBase<T> {
|
|
fn raw_get<'a>(&'a self, idx: uint, _size: uint) -> &'a T {
|
|
&self.data[idx]
|
|
}
|
|
}
|
|
|
|
enum ArrayParent<'parent, T> {
|
|
SliceParent(&'parent ArraySlice<'parent, T>),
|
|
BaseParent(&'parent ArrayBase<T>),
|
|
}
|
|
|
|
/// An immutable slice of a multi-dimensional array
|
|
pub struct ArraySlice<'parent, T> {
|
|
priv parent: ArrayParent<'parent, T>,
|
|
priv idx: uint,
|
|
}
|
|
|
|
impl<'parent, T> Array<T> for ArraySlice<'parent, T> {
|
|
fn dimension_info<'a>(&'a self) -> &'a [DimensionInfo] {
|
|
let info = match self.parent {
|
|
SliceParent(p) => p.dimension_info(),
|
|
BaseParent(p) => p.dimension_info()
|
|
};
|
|
info.slice_from(1)
|
|
}
|
|
|
|
fn slice<'a>(&'a self, idx: int) -> ArraySlice<'a, T> {
|
|
assert!(self.dimension_info().len() != 1,
|
|
"Attempted to slice a one-dimensional array");
|
|
ArraySlice {
|
|
parent: SliceParent(self),
|
|
idx: self.shift_idx(idx)
|
|
}
|
|
}
|
|
|
|
fn get<'a>(&'a self, idx: int) -> &'a T {
|
|
assert!(self.dimension_info().len() == 1,
|
|
"Attempted to get from a multi-dimensional array");
|
|
self.raw_get(self.shift_idx(idx), 1)
|
|
}
|
|
}
|
|
|
|
impl<'parent, T> InternalArray<T> for ArraySlice<'parent, T> {
|
|
fn raw_get<'a>(&'a self, idx: uint, size: uint) -> &'a T {
|
|
let size = size * self.dimension_info()[0].len;
|
|
let idx = size * self.idx + idx;
|
|
match self.parent {
|
|
SliceParent(p) => p.raw_get(idx, size),
|
|
BaseParent(p) => p.raw_get(idx, size)
|
|
}
|
|
}
|
|
}
|
|
|
|
/// A mutable slice of a multi-dimensional array
|
|
pub struct MutArraySlice<'parent, T> {
|
|
priv slice: ArraySlice<'parent, T>
|
|
}
|
|
|
|
impl<'parent, T> Array<T> for MutArraySlice<'parent, T> {
|
|
fn dimension_info<'a>(&'a self) -> &'a [DimensionInfo] {
|
|
self.slice.dimension_info()
|
|
}
|
|
|
|
fn slice<'a>(&'a self, idx: int) -> ArraySlice<'a, T> {
|
|
self.slice.slice(idx)
|
|
}
|
|
|
|
fn get<'a>(&'a self, idx: int) -> &'a T {
|
|
self.slice.get(idx)
|
|
}
|
|
}
|
|
|
|
impl<'parent, T> MutableArray<T> for MutArraySlice<'parent, T> {}
|
|
|
|
#[cfg(test)]
|
|
mod tests {
|
|
use super::*;
|
|
|
|
#[test]
|
|
fn test_from_vec() {
|
|
let a = ArrayBase::from_vec(~[0, 1, 2], -1);
|
|
assert_eq!([DimensionInfo { len: 3, lower_bound: -1 }],
|
|
a.dimension_info());
|
|
assert_eq!(&0, a.get(-1));
|
|
assert_eq!(&1, a.get(0));
|
|
assert_eq!(&2, a.get(1));
|
|
}
|
|
|
|
#[test]
|
|
#[should_fail]
|
|
fn test_get_2d_fail() {
|
|
let mut a = ArrayBase::from_vec(~[0, 1, 2], -1);
|
|
a.wrap(1);
|
|
a.get(1);
|
|
}
|
|
|
|
#[test]
|
|
#[should_fail]
|
|
fn test_2d_slice_range_fail_low() {
|
|
let mut a = ArrayBase::from_vec(~[0, 1, 2], -1);
|
|
a.wrap(1);
|
|
a.slice(0);
|
|
}
|
|
|
|
#[test]
|
|
#[should_fail]
|
|
fn test_2d_slice_range_fail_high() {
|
|
let mut a = ArrayBase::from_vec(~[0, 1, 2], -1);
|
|
a.wrap(1);
|
|
a.slice(2);
|
|
}
|
|
|
|
#[test]
|
|
fn test_2d_slice_get() {
|
|
let mut a = ArrayBase::from_vec(~[0, 1, 2], -1);
|
|
a.wrap(1);
|
|
let s = a.slice(1);
|
|
assert_eq!(&0, s.get(-1));
|
|
assert_eq!(&1, s.get(0));
|
|
assert_eq!(&2, s.get(1));
|
|
}
|
|
|
|
#[test]
|
|
#[should_fail]
|
|
fn test_push_move_wrong_lower_bound() {
|
|
let mut a = ArrayBase::from_vec(~[1], -1);
|
|
a.push_move(ArrayBase::from_vec(~[2], 0));
|
|
}
|
|
|
|
#[test]
|
|
#[should_fail]
|
|
fn test_push_move_wrong_dims() {
|
|
let mut a = ArrayBase::from_vec(~[1], -1);
|
|
a.wrap(1);
|
|
a.push_move(ArrayBase::from_vec(~[1, 2], -1));
|
|
}
|
|
|
|
#[test]
|
|
#[should_fail]
|
|
fn test_push_move_wrong_dim_count() {
|
|
let mut a = ArrayBase::from_vec(~[1], -1);
|
|
a.wrap(1);
|
|
let mut b = ArrayBase::from_vec(~[2], -1);
|
|
b.wrap(1);
|
|
a.push_move(b);
|
|
}
|
|
|
|
#[test]
|
|
fn test_push_move_ok() {
|
|
let mut a = ArrayBase::from_vec(~[1, 2], 0);
|
|
a.wrap(0);
|
|
a.push_move(ArrayBase::from_vec(~[3, 4], 0));
|
|
let s = a.slice(0);
|
|
assert_eq!(&1, s.get(0));
|
|
assert_eq!(&2, s.get(1));
|
|
let s = a.slice(1);
|
|
assert_eq!(&3, s.get(0));
|
|
assert_eq!(&4, s.get(1));
|
|
}
|
|
|
|
#[test]
|
|
fn test_3d() {
|
|
let mut a = ArrayBase::from_vec(~[0, 1], 0);
|
|
a.wrap(0);
|
|
a.push_move(ArrayBase::from_vec(~[2, 3], 0));
|
|
a.wrap(0);
|
|
let mut b = ArrayBase::from_vec(~[4, 5], 0);
|
|
b.wrap(0);
|
|
b.push_move(ArrayBase::from_vec(~[6, 7], 0));
|
|
a.push_move(b);
|
|
let s1 = a.slice(0);
|
|
let s2 = s1.slice(0);
|
|
assert_eq!(&0, s2.get(0));
|
|
assert_eq!(&1, s2.get(1));
|
|
let s2 = s1.slice(1);
|
|
assert_eq!(&2, s2.get(0));
|
|
assert_eq!(&3, s2.get(1));
|
|
let s1 = a.slice(1);
|
|
let s2 = s1.slice(0);
|
|
assert_eq!(&4, s2.get(0));
|
|
assert_eq!(&5, s2.get(1));
|
|
let s2 = s1.slice(1);
|
|
assert_eq!(&6, s2.get(0));
|
|
assert_eq!(&7, s2.get(1));
|
|
}
|
|
|
|
#[test]
|
|
fn test_mut() {
|
|
let mut a = ArrayBase::from_vec(~[1, 2], 0);
|
|
a.wrap(0);
|
|
{
|
|
let mut s = a.slice_mut(0);
|
|
*s.get_mut(0) = 3;
|
|
}
|
|
let s = a.slice(0);
|
|
assert_eq!(&3, s.get(0));
|
|
}
|
|
|
|
#[test]
|
|
#[should_fail]
|
|
fn test_base_overslice() {
|
|
let a = ArrayBase::from_vec(~[1], 0);
|
|
a.slice(0);
|
|
}
|
|
|
|
#[test]
|
|
#[should_fail]
|
|
fn test_slice_overslice() {
|
|
let mut a = ArrayBase::from_vec(~[1], 0);
|
|
a.wrap(0);
|
|
let s = a.slice(0);
|
|
s.slice(0);
|
|
}
|
|
}
|